Sound tape winding reels



DC 2, 1958 G. HERRMANN SOUND TAPE WINDING REELS Filed April 5, 1955Ghfer Herrmann wwf/, www

ATTORNEYS United States Patent O SOUND TAPE 4WINDING nanas GnterHerrmann, Ronnenberg, Hannover, Germany, assignor.` to ProtonaProduktionsgesellschatt fr elektroakustische Gerate G. m. b. H.,Hannover, Germany Application April 5, 1955, Serial No. 499,477

Claims priority, application Germany April 8, 1954 1 Claim. (Cl.242-5512) This invention relates to an arrangement of spools for soundrecording and reproducing apparatus, in particular for magnetic soundapparatus in which the sound carrier consisting of tape is wound fromone spool to `another one. In order to save as much space as possible inmidget apparatus, the spools are closely interspaced. As a rule, thesets of spools are arranged in such a way that the distance between theaxes of the two spools always at least equals the sum of the two spooldiameters. When, for example, the spool to be unwound is stillcompletely lilled, the receiving spool is all empty, that is to say thatfor the preparing of the unwinding operation dead space is required, andthus a minimum dead space which cannot be underpassed with the known setof spools.

In film projection lapparatus it is already known to arrange the tworeels in their connecting line in opposed relation without essentialdead space. The space freed at the one reel is immediately lilled up bythe other reel. However, at thisknown solution the reels of film arearranged on angeless rolls. In film projecting apparatus this solutionis possible, because the film is guided in its lateral perforation bythe maltese cross. The sound tapes of electro-acoustical apparatus,however, are not perforated and need an exact lateral guidance forachieving tight and space saving reels. Moreover, the reels must notslip off the core upon tilting or turning of the apparatus. Pocketsizemagnetic sound recording and reproducing apparatus are expected tooperate reliably in any position whichever.

In the spool arrangement according to the invention this is achieved bythe feature that each spool of a complete set of two has one full-sizeflange and one reduced ange, and that the two spools are put togetherwith the one inverted by 180 relative to the other, so that the twofull-size flanges complete one another in guiding the tape. Thus eachspool completes with its full-size ange the reduced ange of the otherspool in such a way that in any position of the spools the sound carrieris exactly guided in space. The space occupied by the sound carriersteadily moves during the winding process from the one spool to theother, so that there is hardly any more dead space between the twospools and the flanges thereof.

Another advantage of the spool arrangement according to the invention isthe reduction of the weight of the spool owing to the reduction of oneflange. Moreover, spools with one full and one reduced flange are easierand cheaper in production, especially if die-cast or pressure-cast. Thearrangement according to the invention does not impair the exchanging ofspools which can be done as quickly and exactly as with the knownspools.

Furthermore, the guidance of the sound carrier is improved by thearrangement according to the invention, because the unsuspended lengthbetween the two spools is essentially shorter than in the spoolarrangements used so far. The sound carrier cannot sway, wobble or swingany more between the two spools and can thus be exactly wound up on thespools.

Expediently, the spools of each set have parallel axes and parallelturning planes. The arrangement works best when the spools of each sethave parallel axes and the same running planes.

An embodiment of the invention is shown in the drawing, in which Fig. lis a top plan view of the arrangement of spools, and

Fig. 2 is a front elevational view of Fig. l with portions of the tapecut away.

Each set of spools has two identical spools 1 and 2 serving alternatelyas unwinding and receiving spools. Either of the spools 1 and 2 consistsof a hub 3, a reduced ange 4 and a full-size ange 5. In the exampleshown the spools 1 and 2 are put with their hubs 3 on parallel axes 6, 7connected with the drive of the apparatus and turning the spools in thesame direction. 8 indicates the contour of the tape roll being on spool1 and 2. Supposing the left spool 1 being the supply spool andcompletely lilled up, the rolled-up tape moves during the winding fullyto spool 1. If spool 2 is the receiving spool, the rolled-up tape movesfully over to spool 2. Fig. 2 shows an intermediate stage during thewinding. The maior portion of the rolled-up tape is on spool 1 and thesmaller portion on spool 2.

The sound carrier 9 unwound from spool 1 passes the recording head 10and is wound up on spool 2, or reverse. The recording head 10 serves inthe known way for recording or reproducing the sound carrier 9.

What I claim is:

In an electro-acoustical recording apparatus using tape as a recordreceiving means, the combination of two tape winding reels eachconsisting of a hub, a full size ange on one end of said hub, a ange ofreduced size on the other end of said hub, said hubs being on parallelaxes and reversed on said axes with respect to each other with the fullsize flange on the first reel being opposed to the reduced size flangeon the second reel and the reduced size llange on the lirst reel beingopposed to the full size flange on the second reel, said hubs beingspaced from each other a distance only slightly greater than the radiusof the full size flange and the radius of the reduced size llange,whereby a substantially continuously guiding surface for a tapeextending between said hubs is provided on both sides of the tape.

References Cited in the file of this patent UNITED STATES PATENTS602,043 Ecker Apr. 5, 1898 696,234 Gornston Mar. 25, 1902 1,725,443Clayton Aug. 20, 1929 1,771,651 Newman July 29, 1930 2,181,878Eckleberry Dec. 5, 1939

